with numerous tubercles. The carnassial tooth is often, but by no means always, very much larger and especially longer than the rest of the molar and premolar series. It is less pronounced in some of the omnivorous Arctoidea. The skull of the Carnivora is longer in the more primitive types, such as the Canidae, and shorter in the more specialised Felidae. The orbit is hardly ever completely shut off by bone, though the postorbital process of the frontal sometimes approaches the corresponding upward process of the zygomatic arch. The palate, which is completely ossified, sometimes reaches back for some distance behind the teeth; it always extends as far as the last molar. The tympanic bulla is often very inflated, and if flatter, as in the Bears, is at any rate large and conspicuous. The lower jaw has a high coronoid process, and the condyle is transversely elongated, this part of the bone being rolled into an almost cylindrical form; it fits very closely into the glenoid cavity, and the articulation is thereby very strict—an obvious advantage in a creature with so great a need for power of jaw.
Fig. 191.—A, Atlas of Dog. Ventral view, × ½. B, Axis of Dog. Side view, × ⅔. o, Odontoid process; pz, posterior zygapophysis; s, spinous process; sn, foramen for first spinal nerve; t, transverse process; v, vertebrarterial canal. (From Flower's Osteology.)
In the vertebral column the atlas always has large wing-like processes; the spine of the axis vertebra has a long antero-posteriorly elongated form. The transverse processes of the fourth to the sixth cervicals are, as a rule, double. These features, however, though characteristic of the Carnivora are not by any means distinctive. The true sacrum consists of but a single vertebra to which the ilia are attached; but at most two other vertebrae are fused with this. The clavicle is always small and sometimes quite rudimentary, or even absent. The spine of the scapula is well developed, and almost equally divides the
